Mozilla removed the Ask Me Every Time option for cookies in Firefox early this year and they did it silently, so I didn’t notice that I’d accumulated hundreds of cookies because my browser was now accepting them all by default. That is severe bullshit.
I noticed it when I happened to check my cookies. I expect to recognize all the domains where I allow them, but the list was endless and was full of junk I didn’t know. What the hell? Firefox 44:”Ask me every time” cookie option removed explained it: “While it is likely that the majority of users are not affected by the removal of the feature as it was deeply hidden in the options of the browser, those who have made use of it are.” Damn straight.
Cookie Monster, which I used to use, does me no good any more. To do things the way I want I installed Self-Destructing Cookies, which looks like it works well: it accept cookies from sites but then removes them when I close the tab, unless I whitelist the site. Blocking all cookies from a site often breaks the whole thing, but with this, I can look at a site without trouble and when I close the tab the cookies are deleted so if I go back to the site it doesn’t know I was there before. Nice.
I had to go into the cookie settings and remove pretty much everything, because hundreds of sites were whitelisted thanks to Firefox’s incorrect behaviour. Self-Destructing Cookies started deleting cookies, and I restarted the browser to help force a reset of everything. I had to log in to a few sites (and whitelist them) but after a little bit of use it seems OK so far.
Update (2016-10-06): Works a treat on mobile devices, too.